Willis s



.(No Model.)

W. S. RICHARDSON.

PENDANT FOR WATCHES.

No. 372,868. Patented Nov. 8, 1887.

WITNESSES: INVBNTOR:

BY M ATTORNEYS.

UNITED STATES PATENT OFFICE.

WILLIS S. RICHARDSON, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE NEWARK WATCH CASE MATERIAL COMPANY, OF SAME PLACE.

PENDANT FOR WATCHES.

SPECIFICATION forming part of Letters Patent No. 372,868, dated November 8, 1887.

Application filed May 19, 1887. Serial No. 238,778. (No model.)

To all whom it may concern:

Be it known that I, WILLIS S. RICHARD- SON, of Newark, in the county of Essex and State of New Jersey, have invented a new and Improved Safety Attachment for Stem-Winding-\Vatch Crowns, of which the following is a full, clear, and exact description.

My invention relates to an improvement in safety attachments for stemwinding-watch crowns, and has for its object to provide a means whereby the spring of a watchmay be safely wound up without danger of breaking the same, and whereby the device may be simply and quickly adjusted to accommodate any strength of spring, and wherein also the device may be used in connection with any ordinary case without altering the same.

The invention consists in the construction and combination of the several parts, as will be hereinafter fully set forth, and pointed out in the claim.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 is a central longitudinal section through the device and the crown. Fig. 2 is a side elevation of the detached stem. Fig. 3 is a plan view of the same, and Fig. 4 is a longitudinal central seetion through the stem on line 00 as of Fig. 3.

In carrying out the invention the usual crown, B, is provided, into the under side of which an eXteriorly-threaded sleeve, 13, is detachably secured, and upon said sleeve a locknut, I), is screwed,which nut may, if desirable, constitute an integral portion of the crown.

A stem, D, partially of a normal diameter equal to the inner diameter of the sleeve B, is made to project upward into the sleeve. A rectangular longitudinal recess, d, is provided at the lower end of the stem, adapted to take the movement, which lower end is made larger than the body and provided with a shoulder,

11, to receive the lower end of the aforesaid sleeve B, as shown in Fig. 1.

The upper end of the stem D is provided with a circular interiorlythreaded aperture, E, and opposing and aligning longitudinal slots 6, (illustrated in Figs. 1 and 2.) Into the circular aperture thus formed a screw, 0, is entered, having a tapering head, 6', the walls of the said aperture E being also made tapering at the top to normally accommodate the small under tapering portion of the head.

In operation the screw 0 is carried down into the shank a sufficient distance to expand the shank against the walls of the sleeve, so that a tension will be had equal or slightly more than equal to the strength of the spring adapted to be wound by the stem. Thus when the crown is turned in the proper direction the stem will be held sufficiently rigid in connection with the sleeve to wind the spring. When, however, the spring has been wound to the full limit, the next turn of the crown, which will naturally be stronger than the others, as resistance is met with, will cause the sleeve to turn upon the stem, thereby tak ing off any serious or damaging strain which otherwise would be exerted directly upon the spring, causing the same to break.

Having thus fully described my invention, I claim as new and desire to secure by Letters Patent In a stem-winding watch, the combination, with the crown and an eXteriorly-threaded sleeve entered into said crown, of a stern having a threaded aperture in one end and slit diametrically at said end, and a screw having the under side of its head tapered, adapted to exert tension upon the stem, substantially as herein shown and described, and for the pur pose set forth.

WILLIS S. RICHARDSON.

Witnesses:

ALEXANDER MILNE, FREDK. T. J OHNSON. 

